1. Field of Invention
Exercise Device 482/51, 72, 901
Conventional Indoor Rowing Machines (also referred to as “Ergometers” or “Ergs”) generally consist of a horizontally translating seat on rollers 3 riding on a rigid frame 1, a resistance device (typically a rotary device) 4 connected to a pull handle 10 also mounted in-line to the seat on said frame. Foot mounts or stretchers 5 are also positioned appropriately on the rigid frame. The user secures his or her feet to the stretchers 5 and with his or her legs, back, arms, and hands, pulls via the handle on the resistance device to approximate forces on the body similar to the on-water rowing experience. These devices are widely used by the rowing community throughout the year typically with peak usage in colder months.
The Ergs are used for training and for measuring progress of rowers' conditioning as they train over the winter months. During the rowing season, Ergs are used to supplement on-water workouts to maximize conditioning. In addition, among the competitive rowing teams, the “Erg scores” are used as selection criteria of rowers for the fastest boats in various competitions. Also Erg scores are used for comparison of rowers across the country as part of the selection process for the national team boats. The standard used to measure erg scores is a static rowing machine. Thus, coaches need to be able to quickly and easily remove any and all rowing machine accessories and training aids from the rowing machine in order to accurately record and evaluate their rowers' erg scores. These Erg machines are also used by the non-rowing community for general fitness.
Conventional Ergs suffer from several deficiencies as compared to what is experienced in a rowing craft or boat (also referred to as a “Shell”):                Boat side to side balance or Set        Horizontal compliance (energy absorption) that is felt at either end of the stroke (oar entry or Catch, as shown in FIG. 1A and oar exit or Finish, as shown in FIG. 1B)        Buoyant/vertical compliance (energy absorption) at the Catch and the Finish.        
The present invention is an energy absorbing suspension for a rowing machine which addresses conventional erg deficiencies by simulating the on-water motions of a boat through the additions of responsive and compliant roll, pitch, and yaw motions throughout the entire rowing stroke (FIG. 1C).
Since a conventional erg does not offer roll, pitch, and yaw motions, the rower cannot train the same way on the land as on the water, where these motions impact rowing a shell as effectively as possible. When a shell pitches, the bow (front) and stem (rear) of the shell alternately move up and down in an angular motion in response to the rower movements at both the catch and the finish portions of the stroke. The smoother the rower's motions are at the center of rotation, in a plane along the center of the hull, the less pitching the shell will endure. Additionally, as the rower traverses back and forth along the hull, they attempt to do so with very little side-to-side (roll) motion. Rowing with good roll balance allows both oars to stay off the water during the recovery which reduces drag and also allows for optimum power when driving the oars through the water. When pressure is applied to the oars through the rower's push on the boat, even force from both sides of the body is necessary to keep the shell from turning (yawing) about its line of direction. As the shell yaws, a steering correction is required thus slowing the shell down. By minimizing all of these motions, through good rowing technique, the shell will move faster and more efficiently. Therefore, the adding of responsive roll, pitch, and yaw to the erg gives the rower greater opportunity to improve their rowing motion when they cannot be on the water.
2. Related Art
The rowing industry standard for Ergometers is the Concept2, manufactured by Concept2 in Morrisville, Vt. under U.S. Pat. Nos. 4,396,188, 4,875,674, 7,201,708. Numerous alternatives to this embodiment have been developed under such patents as U.S. Pat. Nos. 4,884,800, 4,880,224, 4,772,013, and 4,743,011. Most Ergs have been developed on a stationary frame. A significant drawback to the stationary frame is that it does not provide the energy absorbing downward motion that is experienced in an on-water rowing craft. Numerous studies have indicated that there are a variety of injuries suffered by rowers training on Ergometers (“Impact of Ergometer Design on Hip & Trunk Muscle Activity”, Journal of Sports Science and Medicine, 2005, “Rowing: Injury Prevention and Management”, Australian Institute of Sport).
In an effort to better simulate the on-water experience, the RowPerfect Ergometer, U.S. Pat. No. 5,382,210, was developed with frame and resistance elements that move with the rower in the horizontal direction. Additionally, Concept2 offers a slide as an accessory to their Ergometer to provide a similar horizontal motion. While the horizontal motion embodied in these two developments does improve the feel to a row on the water, they still do not provide any vertical energy absorption that the on-water experience also provides.
Another approach, U.S. Pat. Nos. 7,270,630, 6,991,589, attempts to maximize the exercise experience by varying the front and the back elevation of an Erg to provide an inclined path in both the drive and the recovery portion of the stroke. This design provides vertical movement but only as a fixed position not providing vertical compliance during the stroke.
U.S. Pat. No. 5,441,469(Chern) employs the use of two hydraulic cylinders mounted to a collapsible foot linkage in the rear of a sculling ergometer. In concert with this linkage are two rigid columns centrally mounted in line to the middle and front of the Erg frame. The purpose of this integrated Erg design is to provide a rocking motion at the rear of said machine that better simulates the on-water motion of a shell via the passive resistance of the hydraulic cylinder motion. While Chern offers roll throughout the stroke, pitch compliance is only provided at the finish (the rear of the Erg) since when the rower moves forward on said machine it rocks downward onto a rigid column at the catch. In contrast, the invention described herein provides responsive and compliant roll, pitch, and yaw motion throughout the entire stroke to any rigid frame rowing machine to better simulate the rowing motion one feels in a boat on the water.
Additional on-water experience add-on aftermarket devices have been designed for the Ergometer that simulate the side to side roll motion that is experienced when on the water. One such device is an adaptation to the Erg seat, Core Perform (U.S. Pat. No. 7,452,314), that provides compliance about the fore and aft, or drive axis of the Erg. Another embodiment of this approach is WILIS by Row Balance (U.S. Pat. No. 7,946,964) which features a pivot cradle that the Erg is placed in. This allows the entire Erg, not just the seat, to pivot about the drive axis also simulating the side to side motion experienced on the water. While these devices do provide roll motion, neither of these devices provide any compliance in either roll, pitch, or yaw and therefore offer no protection to the rower from the harshness of a rigid rowing machine.
Another invention that attempts to simulate the on-water experience, Yang (U.S. Pat. No. 4,650,181), offers two degrees of motion, in which Yang refers to as bowing and waving. The first motion is a responsive motion to the rowers movements, pitch compliance, through the use of cushioning springs and the other is a forced, rigid, roll motion through the use of uneven rails. Yang's central fulcrum stand constrains the motion of the base which in turn constrains the motions of the entire device and rower to pitch only by means of the cushioning springs. The second motion offered by Yang's invention is to forcibly roll the rower side to side by riding over the asymmetric, uneven rails of the base throughout the entire rowing motion to ‘increase the player's interest’. Yang's forced roll motion makes it impossible for the rower to make the necessary neuromuscular compensations to attempt a smooth, balanced rowing stroke. Unlike the Yang invention, the EASE invention described here within responds to all of the rower's movements by giving proportional motion feedback in all three degrees of motion (roll, pitch, and yaw). This feedback from the EASE allows the rower to respond and correct their balance. Balanced posture throughout the rower's motion is one of the main objectives of proper rowing on the water.